Continued A/C troubleshooting

[SGT John]

I just need someone to help me break this down for me.


I have isolated my heat exchanger by replacing the monovalve with a ball valve.

I jumpered the aux fan

I jumpered the other set of leads connecting to the receiver/dryer, this should be the compressor right? (a sort of metallic noise comes from there when I touch the leads together.. lasts maybe 1/4 of a second.. sort of a clang or click)

I took the car to Firestone and had them check out my AC before I jumpered the compressor. The note on my invoice said

!! PUT ENOUGH FREON INTO SYSTEM THAT COMPRESSOR SHOULD ENGAGE BUT SEEMS TO HAVE ELECTRICAL AND CONTROL PROBLEMS, RECOMMEND DEALER OR IMPORT SHOP !!!!!

Funny.. looked like the same amount of charge I had in the system.. they didn't evac it or anything.. just topped it off then scratched their heads. I am impressed with their service department though. They gave me a 20 dollar discount when I told the guy I didn't think it was fair that I paid 45 bucks for a top-off, and they had no clue what was wrong with the system.

So confirm these things for me please:

1. My compressor functions the same weather jumpered or hooked to the CCU, so I think the CCU is good.
2. My low side pressure drops as I accelerate, so I think my compressor is good.
3. Firestone agrees that I have the proper level of refrigerant in my car.. 60psi at Idle/35psi at 2k rpms on the low and 150 at idle, then 160 at 2krpms on the high...
4. I think I have a blockage somewhere, or too much lube in my system. Does everyone agree my next step should be evac the system, purge with acetone, and replace the receiver/dryer and expansion valve? My normal import mechanic estimates they can do it for around 200 bucks, and my price will drop more because I will be supplying the expan and dryer... unfortunately my import mechanic is the only one nearby and has a backlog of about 8 days.. so it will be NEXT Tuesday before they can even get me in the bay.

Last question... does everyone agree that R12 will give me a cooler system? One of the mechanics I deployed with has his cert and can buy me R-12. Is it worth it? How much do we need to buy?

[Brian Carlton]

You begin a brand new thread and assume that all readers remember the symptoms from previous threads.

I don't and I'm sure others won't as well.

If you're going to start from the beginning.......better describe the symptoms as well.

[SGT John]

Originally Posted by SGT John

60psi at Idle/35psi at 2k rpms on the low and 150 at idle, then 160 at 2krpms on the high...

Sorry to make things difficult.

My a/c doesn't blow cold air.
The low side pipe doesn't even get cold.


Everything else that I have done or have observed is listed in post #1

Hope that clears it up.

[Brian Carlton]

Originally Posted by SGT John

Sorry to make things difficult.

My a/c doesn't blow cold air.
The low side pipe doesn't even get cold.


Everything else that I have done or have observed is listed in post #1

Hope that clears it up.

If the compressor works properly and you've got nothing on the low side.........after the expansion valve..........then the valve is the culprit. Was it changed recently or is it original?

[Arthur Dalton]

...or there is air in the system...never trust a topping off unless you know the system was properly charged before it needed topping.
Some clowns just think they can charge a system w/o evacuation..they then wind up with high/low pressures on the gauge, but no refrigeration to speak off...b/c the system is full of air.....

[SGT John]

Originally Posted by Brian Carlton

If the compressor works properly and you've got nothing on the low side.........after the expansion valve..........then the valve is the culprit. Was it changed recently or is it original?

I don't understand what you mean by "after the expansion valve" Is it just a description of where the part is on the system? I gave the readings for my high-side port and my low-side port, at idle and at 2k rpms. The rest is you teaching me, Sensei.


I don't know if the valve is the original or not. I know that I have a reman compressor because I saw the sticker this weekend when I was looking for a part number to do a worst case scenario estimate for my wife

looking again to try and tell you if it was original or not, I started the engine just for kicks and when I am closer to it I can hear a sort of squelching in that area... like water moving through a pipe I guess...

[SGT John]

That makes sense Arthur... so in that case, still, the best way to go is an evac and flush right?

does anyone think I should not go back to R-12?

[Arthur Dalton]

Correct.
What does the eyesight glass look like????

[Brian Carlton]

Originally Posted by SGT John

I don't understand what you mean by "after the expansion valve" Is it just a description of where the part is on the system? I gave the readings for my high-side port and my low-side port, at idle and at 2k rpms. The rest is you teaching me, Sensei.

The expansion valve is the end of the high pressure system and the beginning of the low pressure system. After the valve is the evaporator. If there is no flow to this area, my suspicion is that the expansion valve is blocked in some fashion.

If there is flow, but it's not satisfactory to cool the vehicle, then Arthur's suggestion that the system is full of air is valid.

[SGT John]

grey, with no movement visible..ever.

[Arthur Dalton]

Originally Posted by SGT John

grey, with no movement visible..ever.

Pull the eyesight cover off..

[SGT John]

::scratches head and runs out to car with a flashlight::

[SGT John]

there seems to be nothing to remove. I am going to upload and post a pic I took earlier today.

ETA PHOTO

[Arthur Dalton]

That's OK..some don't have it , some just get thrown out.
It is a little inverted plastic cup that keeps the dirt off the actual glass..if you go clean it w/Q-tip and you can definately see GLASS, that is fine.
Does the high side pressure line between the drier and the condenser get hot ??? put yor hand right on it.

[SGT John]

gets rather hot. I could hold onto it, but wouldn't want to for very long.